That I've personally seen on film? 1.Holmes (Cooney, pretty much any fight) 2.Liston (pretty much any fight) 3.Quartey (Park, Oscar) 4.Louis (Galento) 5.Hearns (Benitez, etc.) honourable mention: jones (94-98), Billy Conn, Oscar (chavez fights), Whitaker
Cant really put it in a list right now, but along with those already mentioned, Harold Johnson's jab was a thing of beauty. After watching Sumbu Kalmabay fights, I gotta say that he had one hell of a jab when he wanted to used it to.
Good call, id give his first fight with Herol Graham a shout out to. A more slippery, awkward and hard to hit middleweight you could not find in that era, yet Sumbu managed to tag him consistently with the jab and outbox him as he forced Herol to come to him.